Residents gather to watch fireworks rehearsals ahead of the upcoming 100th anniversary of the founding of China's ruling Communist Party in Beijing on Tuesday, June 22, 2021. Chinese authorities have closed Beijing's central Tiananmen Square to the public, eight days ahead of a major celebration being planned to mark the 100th anniversary of the founding of the ruling Communist Party. (Photo by Ng Han Guan/AP Photo)

A delegate poses for a photo at the end of the closing ceremony of the 20th National Congress of the Chinese Communist Party in front of the Great Hall of the People in Beijing, China, on Saturday, October 22, 2022. President Xi Jinping is officially set for a third term surrounded by allies, after key Communist Party officials without close ties to the Chinese leader exited the nation's top leadership body. (Photo by Bloomberg)

People look at buildings displaying a light show on the eve of the 100th anniversary of the Chinese Communist Party in Beijing on June 30, 2021. (Photo by Noel Celis/AFP Photo)

This photo taken on October 8, 2017 shows dancers posing in formation to celebrate the upcoming Party Congress, in Rongan in China' s southern Guangxi region. China will convene its 19 th Party Congress on October 18, state media said, a key meeting held every five years where President Xi Jinping is expected to receive a second term as the ruling Communist Party' s top leader. (Photo by AFP Photo/Stringer)

Attendants wait for visitors to the the exhibition entitled “Forging Ahead in the New Era”, showing the country's achievements during his past two terms, at the Beijing Exhibition Center in Beijing on October 12, 2022, ahead of the 20th Communist Party Congress meeting. (Photo by Noel Celis/AFP Photo)

A woman sells Cuban Communist Party (PCC) official newspaper Granma with a picture of former Cuba's President Fidel Castro at the front page, at the main touristic road in Havana, Cuba, September 14, 2016. (Photo by Alexandre Meneghini/Reuters)

Buzludzha is a historical peak in the Central Stara Planina, Bulgaria and is 1441 metres high. In 1868 it was the place of the final battle between Bulgarian rebels led by Hadji Dimitar and Stefan Karadzha and the Ottoman Empire. The Buzludzha Monument on the peak was built by the Bulgarian communist regime to commemorate the events in 1891 when the socialists led by Dimitar Blagoev assembled secretly in the area to form an organised socialist movement with the founding of the Bulgarian Social Democratic Party, a fore-runner of the Bulgarian Communist Party. The Monument was opened in 1981. No longer maintained by the Bulgarian government, it has fallen into disuse. Buzludzha is reached by a 12 km side road from the Shipka Pass.

Hospitality staff members laugh as they stand on Tiananmen Square before the closing ceremony of China's 19th Party Congress at the Great Hall of the People in Beijing, Tuesday, October 24, 2017. The ruling Communist Party on Tuesday formally lifted Xi Jinping's status to China's most powerful ruler in decades, setting the stage for the authoritarian leader to tighten his grip over the country while pursuing an increasingly muscular foreign policy and military expansion. (Photo by Mark Schiefelbein/AP Photo)